A facile crosslinking method for polybenzimidazole membranes toward enhanced organic solvent nanofiltration performance

Herein, a facile method for crosslinking polybenzimidazole membranes applied in organic solvent nanofiltration (OSN) using an aqueous potassium permanganate (KMnO4) solution is presented. The membranes were crosslinked under mild water-based conditions at room temperature for less than 4 h. The crosslinked polybenzimidazole OSN membrane exhibited superior separation performance and enhanced stability in various solvents, including dimethylformamide and N-methyl-2-pyrrolidone. The crosslinked membranes exhibited greater than 90% rejection rate for dyes with molecular weights in the range of 327 to 1017 Da, and they were compatible with various common organic solvents such as ethanol, isopropyl alcohol, acetone, and dimethylformamide. Furthermore, no significant change in the membrane performance was observed when polar and nonpolar solvents were used in filtration experiments.

Automated summary

A facile method for crosslinking polybenzimidazole membranes for organic solvent nanofiltration using an aqueous potassium permanganate solution was presented. The crosslinked membranes exhibited superior separation performance and enhanced stability in various solvents.